// 云函数入口文件
const cloud = require('wx-server-sdk')

cloud.init()
const db=cloud.database();
const _ = db.command
// 云函数入口函数
exports.main = async (event, context) => {
    var data=event.collect

    return await db.collection('topic').
    where({
      _id:_.in(data)
    })  
    .orderBy('lastReplytime','desc')
    .get()



}